diff options
Diffstat (limited to 'python')
| -rw-r--r-- | python/vyos/utils/io.py | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/python/vyos/utils/io.py b/python/vyos/utils/io.py index 77e30cbb0..58ceb3476 100644 --- a/python/vyos/utils/io.py +++ b/python/vyos/utils/io.py @@ -55,8 +55,25 @@ def ask_input(question, default='', numeric_only=False, valid_responses=[], return response def ask_yes_no(question, default=False) -> bool: - """Ask a yes/no question via input() and return their answer.""" - from sys import stdout + """Ask a yes/no question via input() and return their answer. + + Raises EOFError immediately if stdin is not a TTY (e.g. non-interactive + scripts), instead of ever calling input(). A silent default here has + caused real incidents (T9185): a caller that forgets to guard an + interactive-only prompt gets no error and no visible hang, just a + process quietly pegging a core. Callers that are meant to run + non-interactively must check for that explicitly (see the no_prompt + parameter used across config_mgmt.py/backend.py) rather than rely on + this function to fall back to a default. + """ + from sys import stdin, stdout + + if not stdin.isatty(): + raise EOFError( + f'Cannot prompt "{question}" ([Y/n] default={default}): ' + 'stdin is not a TTY. Pass an explicit non-interactive option ' + '(e.g. no_prompt/-y) instead of relying on ask_yes_no().' + ) default_msg = "[Y/n]" if default else "[y/N]" while True: try: |